This invention relates to childrens' toys and, more particularly, to toy masks capable of transmitting and disguising the voice of the wearer.
It has been recognized for a long time that children of a certain age derive a great deal of pleasure from making noise. Children who are somewhat older enjoy communicating with each other using secret codes or languages that parents and others, including other children, cannot understand. A prior art toy mask that disguised the voice of the wearer and also permitted the making of Martian-like sounds is shown in D. E. Jennings, et al. Pat. No. 4,400,591, issued Aug. 23, 1983. In accordance with the disclosure of that patent, electronic circuitry was interposed between a microphone and a loudspeaker mounted in the helmet. The electronics multiplied the voice signal with the output of an oscillator to derive output signals whose amplitudes were the logarithms of the signal inputs at frequencies determined by the algebraic sum and difference of the voice frequency fundamental and the oscillator frequency. None of the original input wave forms appears in the output so that a considerable alteration of the original voice was obtained. The Jennings patent helmet thus seemed to satisfy one of the desires of the child in that it produced unusual speech-releated noise signals. It does not, however, enable children to actually communicate intelligible speech to each other.
While the analog multiplier circuitry taught in the Jennings patent is effective to provide an appropriate noise output, integrated circuit multipliers suffer from two disadvantages; they are expensive and tend to consume a great deal of power thereby shortening useful battery life.
Other helmet communications systems are known such as that shown in M. E. White Pat. No. 4,152,553 issued May 1, 1979 which include sophisticated two-way radio transmitting and receiving equipment. Such systems while effective for intelligible speech communications, lack suitability for use as low-cost noise-producing toys.